Weaving-free interchange with few bridges and exterior exits and entrances only

ABSTRACT

The present invention is a traffic-weaving-free grade-separated road junction that provides for continuous flow of traffic and provides exterior exits and entrances only (i.e., it provides right-side exits and entrances only where the convention is for traffic to keep to the right, but provides left-side exits and entrances only where the convention is for traffic to keep to the left). Two of the embodiments have two loop ramps and require as few as two bridges. Two other embodiments have no loop ramps and require as few as three bridges. In addition, four other embodiments have one loop ramp and require as few as three bridges; two other embodiments have no loop ramps and require as few as four bridges; and two embodiments provide U-turn ramps, have no loop ramps, and require as few as three bridges. Compared to prior art junctions that also provide for continuous flow of traffic, avoid weaving, and provide exterior exits and entrances only, the present invention can be constructed with fewer bridges and/or fewer loop ramps. Therefore, the present invention provides reduced structure-related costs and/or increased safety and speed for drivers. In addition, because it can be constructed with fewer bridges than said prior art junctions, the present invention provides lower aesthetic impacts and other environmental costs. Finally, the embodiments of the present invention provide an additional set of design options for road engineers to choose from when designing within particular constraints of right-of-way, topography, and other factors.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority of U.S. Provisional Application No.61/413432, filed 13 Nov. 2010, which is hereby incorporated by referencein its entirety.

BACKGROUND OF THE INVENTION

This invention relates to grade-separated junctions for intersectingroads, and more particularly, to grade-separated junctions that providefor the continuous and weaving-free flow of traffic on intersectingroads, and that provide exterior exits and entrances only. For thepurposes of this patent, the term ‘exterior exit’ refers to a right-sideexit where the convention is for traffic to keep to the right, butrefers to a left-side exit where the convention is for traffic to keepto the left, while the term ‘exterior entrance’ refers to a right-sideentrance where the convention is for traffic to keep to the right, butrefers to a left-side entrance where the convention is for traffic tokeep to the left.

Grade-separated junctions are more commonly known as interchanges. Thereare many interchange configurations that permit free flow of traffic fortraffic traveling directly through the interchange or turning left orright onto the intersecting road or roads. However, these existingconfigurations have disadvantages in one or more of the followingaspects: safety, traffic capacity, construction costs, maintenancecosts, modification costs, right-of-way costs, or environmental costs.

The ‘cloverleaf’ configuration (U.S. Pat. No. 1,173,505), because itrequires as few as one bridge, has relatively low structure-relatedcosts, but as is well-known, the weaving of traffic exiting from andentering onto the mainlines reduces the safety and capacity of theinterchange. A common treatment of interchanges is the addition ofseparate collector-distributor roads. This removes weaving-relatedproblems from the mainlines, but weaving still exists on thecollector-distributor roads. In addition, the addition ofcollector-distributor roads increases structure-related costs andright-of-way requirements. Another disadvantage of the cloverleafconfiguration is that the loop ramps of the cloverleaf result in largeright-of-way requirements and/or low design speeds.

Several weaving-free interchange configurations have since beendeveloped. The lour-level directional' or ‘stack’ configuration (seeExhibit 10-33 B and C from A Policy on the Geometric Design of Highwaysand Streets, Fourth Edition, by the American Association of StateHighway and Transportation Officials) provides improved capacity andsafety, but has high structure-related costs due to the length andheight of structures required. In addition, because of the height ofsome of the structures, there can be problems with icing in coldconditions. Another problem is that the height of the structures can beproblematic from an urban design and aesthetic perspective. Finally,future modifications of the configuration are expensive.

The semi-directional (see Exhibit 10-33 A of A Policy on the GeometricDesign of Highways and Streets, Fourth Edition, by the AmericanAssociation of State Highway and Transportation Officials) or ‘turbine’configuration can have somewhat lower structure-related costs than thefour-level directional. An uncommon modification of the ‘turbine’ (seeFig. VB6.11 from VicRoads Supplement to the Austroads Guide to RoadDesign Part 4C—Interchanges, Rev. 1.1), sometimes called the ‘windmill’,can have still lower structure-related costs, as it can be constructedusing as few as five bridges.

Two lower-cost weaving-free modifications of the cloverleafconfiguration also exist, each with two loop ramps. One, a ‘semidirect’interchange (see Exhibit 10-33 of A Policy on the Geometric Design ofHighways and Streets, Fourth Edition, by the American Association ofState Highway and Transportation Officials), sometimes called a‘clover-stack’, still has relatively high structure-related costs due tothe height and length of two of the structures required. Another type ofsemidirect interchange (see FIG. 10 of “A model for calculating optimalvertical alignments of interchanges” by Lee and Cheng, TransportationResearch Part B, Vol. 5, Issue 5, pp. 423-445), sometimes called a‘clover-turbine’, can have somewhat lower structure-related costs.

Nevertheless, the ‘turbine’, ‘windmill’, ‘clover-stack’, and‘clover-turbine’ configurations are inappropriate for many applicationsbecause of excessively high structure-related costs.

Five other prior weaving-free modifications of the cloverleafconfiguration exist. A rare such configuration, which has four loopramps and requires as few as five bridges, is sometimes called a‘braided’ cloverleaf. A built example of this configuration exists nearFrankfurt, Germany, at the junction of the bundesautobahnen 3 and 5.Another configuration is shown in FIGS. 3h and 3i of InternationalPatent Application Publication No. WO 2004/104301. This configurationhas four loop ramps, requires as few as five bridges, and requires avery large right-of-way. The remaining three prior weaving-freemodifications of the cloverleaf configuration each have two loop rampsand require as few as three bridges. The first is the ‘continuous flowcloverleaf-type interchange’, described in U.S. Pat. No. 4,861,184. Thesecond is sometimes called the ‘partially-unrolled cloverleaf’. A builtexample of this configuration exists near Reading, UK, at the junctionof the M4 and A329 motorways. The third, more common configuration issometimes called the ‘clovermill’, because it uses two left-turn rampswith a form similar to those of the ‘windmill’. A built example of thisconfiguration exists at the junction of Interstate 395 and King St. inAlexandria, Va., USA.

There are numerous existing interchange configurations where some or allof the exits or entrances are interior rather than exterior (i.e., wheresome exits or entrances are located at the left side of the road wherethe convention is for traffic to keep to the right, or where some exitsor entrances are located at the right side of the road where theconvention is for traffic to keep to the left). Some examples are foundin French Pat. No. 2,442,915, and U.S. Pat. No. 1,689,161, U.S. Pat. No.2,941,454, U.S. Pat. No. 3,107,590, U.S. Pat. No. 7,425,104, and someembodiments of U.S. Pat. No. 4,630,961. These configurations aregenerally deprecated for system interchange applications becauseinterior exits, as defined here, have been recognized as causing safetyand operational problems.

All prior existing weaving-free interchange configurations that providefor continuous flow of traffic and that provide exterior exits andentrances only require three or more bridges. All prior existingweaving-free interchange configurations that provide for continuous flowof traffic, have no loop ramps, and provide exterior exits and entrancesonly require five or more bridges. Because reducing the number ofstructures in an interchange tends to reduce structure-relatedcosts—that is, construction, maintenance, and modification costs—as wellas aesthetic impacts and other environmental costs, there is a need fora weaving-free interchange configuration that provides for continuousflow of traffic, provides exterior exits and entrances only, and can beconstructed with fewer than three bridges. In addition, because loopramps provide lower capacity and safety for a given amount ofright-of-way, there is also a need for a weaving-free interchangeconfiguration that provides for continuous flow of traffic, has no loopramps, provides exterior exits and entrances only, and can beconstructed with fewer than five bridges. Finally, because priorinterchange configurations may not be appropriate for some sites withparticular constraints of right-of-way, topography, and other factors,there is a general need for new interchange configurations to providemore design options to transportation planners and engineers.

BRIEF SUMMARY OF THE INVENTION

The present invention is a traffic-weaving-free grade-separated roadjunction that provides for continuous flow of traffic and providesexterior exits and entrances only. Two of the embodiments have two loopramps and require as few as two bridges. Two other embodiments have noloop ramps and require as few as three bridges. In addition, four otherembodiments have one loop ramp and require as few as three bridges; twoother embodiments have no loop ramps and require as few as four bridges;and two embodiments provide U-turn ramps, have no loop ramps, andrequire as few as three bridges. Compared to prior art junctions thatalso provide for continuous flow of traffic, avoid weaving, and provideexterior exits and entrances only, the present invention can beconstructed with fewer bridges and/or fewer loop ramps. Therefore, thepresent invention provides reduced structure-related costs and/orincreased safety and speed for drivers. In addition, because it can beconstructed with fewer bridges than said prior art junctions, thepresent invention provides lower aesthetic impacts and otherenvironmental costs. Finally, the embodiments of the present inventionprovide an additional set of design options for road engineers to choosefrom when designing within particular constraints of right-of-way,topography, and other factors.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF DRAWINGS

FIGS. 1 through 30 are plan view schematics of the various embodimentsof the invention. Note that the drawings of FIGS. 2, 4, 6, 8, 10, 12,14, 16, 18, 20, 22, 24, 26, 28, and 30 are based on horizontalreflections of the drawings of FIGS. 1, 3, 5, 7, 9, 11, 13, 15, 17, 19,21, 23, 25, 27, and 29, respectively.

FIG. 1 shows the arrangement of road surfaces in a first embodiment,which has two loop ramps and requires as few as two bridges;

FIG. 2 shows a second embodiment, which has two loop ramps and requiresas few as two bridges.

FIG. 3 shows the arrangement of road surfaces in a third embodiment,which has no loop ramps and requires as few as three bridges;

FIG. 4 shows a fourth embodiment, which has no loop ramps and requiresas few as three bridges.

FIG. 5 shows the arrangement of road surfaces in a fifth embodiment,which has no loop ramps and requires as few as three bridges. U-turnramps are also provided for each leg of the interchange;

FIG. 6 shows a sixth embodiment of the invention, which has no loopramps and requires as few as two bridges. U-turn ramps are also providedfor each leg of the interchange.

FIG. 7 shows the arrangement of road surfaces in a seventh embodiment,which has one loop ramp and requires as few as three bridges;

FIG. 8 shows an eighth embodiment, which has one loop ramp and requiresas few as three bridges.

FIG. 9 shows the arrangement of road surfaces in a ninth embodiment,which has one loop ramp and requires as few as three bridges;

FIG. 10 shows a tenth embodiment of the invention, which has one loopramp and requires as few as three bridges.

FIG. 11 is a plan view schematic of the arrangement of road surfaces inan eleventh embodiment, which has no loop ramps and requires as few asfour bridges;

FIG. 12 shows a twelfth embodiment of the invention, which has no loopramps and requires as few as four bridges.

FIG. 13 is a plan view schematic showing a possible arrangement ofoverpasses and underpasses for the first embodiment of the invention;

FIG. 14 is a plan view schematic showing a possible arrangement ofoverpasses and underpasses for the second embodiment of the invention.

FIG. 15 is a plan view schematic showing a possible arrangement ofoverpasses and underpasses for the third embodiment of the invention;

FIG. 16 is a plan view schematic showing a possible arrangement ofoverpasses and underpasses for the fourth embodiment of the invention.

FIG. 17 is a plan view schematic showing a possible arrangement ofoverpasses and underpasses for the fifth embodiment of the invention;

FIG. 18 is a plan view schematic showing a possible arrangement ofoverpasses and underpasses for the sixth embodiment of the invention.

FIG. 19 is a plan view schematic showing a possible arrangement ofoverpasses and underpasses for the seventh embodiment of the invention;

FIG. 20 is a plan view schematic showing a possible arrangement ofoverpasses and underpasses for the eighth embodiment of the invention.

FIG. 21 is a plan view schematic showing a possible arrangement ofoverpasses and underpasses for the ninth embodiment of the invention;

FIG. 22 is a plan view schematic showing a possible arrangement ofoverpasses and underpasses for the tenth embodiment of the invention.

FIG. 23 is a plan view schematic showing a possible arrangement ofoverpasses and underpasses for the eleventh embodiment of the invention;

FIG. 24 is a plan view schematic showing a possible arrangement ofoverpasses and underpasses for the twelfth embodiment of the invention.

FIG. 25 is a plan view schematic showing another possible arrangement ofoverpasses and underpasses for the first embodiment of the invention;

FIG. 26 is a plan view schematic showing another possible arrangement ofoverpasses and underpasses for the second embodiment of the invention.

FIG. 27 is a plan view schematic showing another possible arrangement ofoverpasses and underpasses for the third embodiment of the invention;

FIG. 28 is a plan view schematic showing another possible arrangement ofoverpasses and underpasses for the fourth embodiment of the invention.

FIG. 29 is a plan view schematic showing another possible arrangement ofoverpasses, underpasses, and right-turn ramps for the third embodimentof the invention;

FIG. 30 is a plan view schematic showing another possible arrangement ofoverpasses, underpasses, and right-turn ramps for the fourth embodimentof the invention.

DETAILED DESCRIPTION OF THE INVENTION

The inventive matter of the present invention is the arrangement of roadsurfaces relative to one another. Specific geometric features such asthe horizontal and vertical alignments are not claimed as the inventivematter in this invention. As with any interchange configuration, apractitioner with ordinary skill in the art of geometric design ofroadways will determine the most appropriate geometry to apply to thevarious embodiments of this invention by considering relevant designstandards and design criteria particular to a given site of interest.

It will be obvious to the practitioner of ordinary skill in the art ofgeometric design of roadways that, in any of the embodiments of thisinvention, one or more road surfaces may be omitted as desired by thepractitioner utilizing the current invention; in addition, it will beobvious that one or more road surfaces may be added as desired by thepractitioner utilizing the current invention. Such modifications arecommonly made to standard interchange configurations, such as thosementioned in the accounting of prior art above.

Note that in the descriptions that follow, it is assumed that theinvention is to be applied to roads where the convention is for trafficto keep to the right. It will be obvious to a person of ordinary skillin the art how to modify the description when the invention is to beapplied instead to roads where the convention is for traffic to keep tothe left.

No right-turn ramps are drawn in the schematics of FIGS. 1 to 12. Itwill be obvious to a practitioner with ordinary skill in the art ofgeometric design of roadways how best to add right-turn ramps to anyembodiment of the present invention. Of the numerous interchangeconfigurations with right-side exits and entrances only that have beendeveloped, there is a wide variety of different arrangements ofmainlines and left-turn ramps relative to one another, and the diversityof configurations practitioners have devised, and continue to devise, isan indication that devising such arrangements is not obvious; however,there is a much smaller variety of feasible arrangements of right-turnramps relative to the mainlines and left-turn ramps in interchanges withright-side exits and entrances only. Thus, it is obvious to thepractitioner of ordinary skill how to devise such arrangements. Wherethe exits for the right-turn and left-turn ramps are located alongsubstantially the same length of road, a right-side exit to a right-turnramp can either be located to the right or the left of the exit for theadjacent left-turn ramp, and where the entrances for the right-turn andleft-turn ramps are located along substantially the same length of road,a right-side entrance from a right-turn ramp can either be located tothe right or the left of the entrance for the adjacent left-turn ramp.Clearly, there are very few possible arrangements. Because it is obviousto a practitioner of ordinary skill how to best arrange right-turn rampsin interchanges with right-side exits and entrances, and because thereare numerous existing constructed precedents of the already scarcenumber of different arrangements or right-turn ramps in variousinterchanges with right-side exits and entrances, right-turn ramps havenot been included in FIGS. 1 to 12.

FIGS. 13 through 30 show several embodiments of the present inventionwith possible arrangements of right-turn ramps. The arrangements ofright-turn ramps in FIGS. 13 through 28 are the most commonarrangements; FIGS. 29 and 30 show possible alternative arrangementswhere the exits to and entrances from two right-turn ramps are locatedto the left of the adjacent left-turn exits and entrances, from theperspective of a driver traveling to, along, and exiting from theright-turn ramp. A similar arrangement of right turn ramps is seen inthe turbine interchange of Belgian Pat. No. 638,746 and No. 641,129.However, all of the embodiments illustrated in FIGS. 13 through 30 maybe constructed with a variety of arrangements of right-turn ramps otherthan those illustrated. As described above, an exit to a givenright-turn ramp can either be located to the right or the left of theexit for the adjacent left-turn ramp, and an entrance from a right-turnramp can either be located to the right or the left of the entrance forthe adjacent left-turn ramp.

In the following descriptions, three abbreviations are used: ‘RS’ standsfor ‘road surface’, ‘RSs’ stands for ‘road surfaces’, while ‘GSC’ standsfor ‘grade-separated crossing’.

FIG. 1 is a plan view schematic of the arrangement of roadways in afirst embodiment of the invention. This embodiment has two loop rampsand requires as few as two bridges. RSs 1, 2, 3, and 4 are commonlycalled mainlines. RS 1 is provided for through traffic traveling fromthe extremity of the junction 37 to extremity of the junction 38. RS 2is provided for through traffic traveling from the extremity of thejunction 38 to extremity of the junction 37. RS 3 is provided forthrough traffic traveling from the extremity of the junction 39 toextremity of the junction 40. RS 4 is provided for through traffictraveling from the extremity of the junction 40 to extremity of thejunction 39.

RSs 5, 6, 7, and 8 are commonly called left-turn ramps. RS 5 is providedfor through traffic traveling from the extremity of the junction 37 toextremity of the junction 40. RS 6 is provided for through traffictraveling from the extremity of the junction 38 to extremity of thejunction 39. RS 7 is provided for through traffic traveling from theextremity of the junction 39 to extremity of the junction 37. RS 8 isprovided for through traffic traveling from the extremity of thejunction 40 to extremity of the junction 38.

At the extremity of the junction 37, RS 1 is disposed laterally betweenRS 2 and RS 5, and RS 2 is disposed laterally between RS 7 and RS 1. Atthe extremity of the junction 38, RS 1 is disposed laterally between RS2 and RS 8, and RS 2 is disposed laterally between RS 6 and RS 1. At theextremity of the junction 39, RS 4 is disposed laterally between RS 6and RS 3, and RS 3 is disposed laterally between RS 4 and RS 7. At theextremity of the junction 40, RS 3 is disposed laterally between RS 5and RS 4, and RS 4 is disposed laterally between RS 3 and RS 8.

The above description of RSs 1 through 8 also applies to FIGS. 2 through30.

Note again that specific geometric features such as horizontal andvertical alignments are not claimed as the inventive matter in thisinvention. The arrangements of road surfaces are defined by theirpositions relative to one another—for example, in the embodiment of FIG.1, RS 1, at the extremity of the junction 37, is disposed laterallybetween RS 2 and RS 5, and at the extremity of the junction 38, it isdisposed laterally between RS 2 and RS 8, and between the extremities ofthe junction 37 and 38, it has grade-separated crossing with RSs 8, 4,3, 7, 5, and 6, and these grade-separated crossings occur in aparticular order relative to one another. Note also that the phrase“disposed laterally between” in this patent does not imply an identicalvertical elevation. For example, in the embodiment of FIG. 1, at theextremity of the junction 37, RS 1 may be at a vertical elevationdistinct from that of RS 2 and RS 5. In most cases, a practitionerconstructing the embodiment will place RS 1 at a vertical elevationsubstantially similar to that of RS 2 and RS 5; however, there may becases where it is preferred not to do so. This kind of practice is alsowell-known to practitioners of the art of geometric design of roadways,and numerous interchanges of various configurations have been thusconstructed.

RS 1 intersects with RS 4 at GSC 9; RS 1 intersects with RS 3 at GSC 10;RS 2 intersects with RS 3 at GSC 11; RS 2 intersects with RS 4 at GSC12; RS 5 intersects with RS 4 at GSC 13; RS 5 intersects with RS 3 atGSC 14; RS 6 intersects with RS 3 at GSC 15; RS 6 intersects with RS 4at GSC 16; RS 1 intersects with RS 5 at GSC 17; RS 1 intersects with RS6 at GSC 18; RS 2 intersects with RS 6 at GSC 19; and RS 2 intersectswith RS 5 at GSC 20.

The above description of GSCs 9 through 20 also applies to FIGS. 2through 12. Note that RSs 1 through 6 are arranged, relative to eachother, in the same arrangement in all embodiments of the presentinvention. The various embodiments of the present invention are formedby providing different arrangements of other RSs, such as 7, 8, andothers described below, relative to RSs 1 through 6.

RS 1 intersects with RS 8 at GSC 21; RS 1 intersects with RS 7 at GSC22; RS 2 intersects with RS 7 at GSC 23; RS 2 intersects with RS 8 GSC24; RS 5 intersects with RS 8 at GSC 25; RS 5 intersects with RS 7 atGSC 26; RS 6 intersects with RS 7 at GSC 27; RS 6 intersects with RS 8at GSC 28; RS 8 intersects with RS 8 at GSC 29, RS 8 intersects with RS4 at GSC 30; RS 8 intersects with RS 3 at GSC 31; RS 8 intersects withRS 7 at GSC 32. RS 7 intersects with RS 7 at GSC 33; RS 7 intersectswith RS 3 at GSC 34; RS 7 intersects with RS 4 at GSC 35; and RS 7intersects with RS 8 at GSC 36.

In the following descriptions, the phrase ‘is disposed along’ stands for‘is disposed intermediately along the length of’. For example, thesentence that follows means ‘GSC 21 is disposed intermediately along thelength of RS 1 between the extremity of the junction 37 and GSC 9’.

GSC 21 is disposed along RS 1 between the extremity of the junction 37and GSC 9. GSC 9 is disposed along RS 1 between GSC 21 and GSC 10; GSC10 is disposed along RS 1 between GSC 9 and GSC 22; GSC 22 is disposedalong RS 1 between GSC 10 and GSC 17; and GSC 17 is disposed along RS 1between GSC 17 and GSC 18. SC 19 is disposed along RS 2 between theextremity of the junction 38 and GSC 20; GSC 20 is disposed along RS 2between GSC 19 and GSC 23; GSC 23 is disposed along RS 2 between GSC 11and GSC 23; GSC 11 is disposed along RS 2 between GSC 23 and GSC 12; andGSC 12 is disposed along RS 2 between GSC 11 and GSC 24. GSC 25 isdisposed along RS 5 between the extremity of the junction 37 and GSC 13;GSC 13 is disposed along RS 5 between GSC 25 and GSC 14; GSC 14 isdisposed along RS 5 between GSC 13 and GSC 26; GSC 26 is disposed alongRS 5 between GSC 14 and GSC 17; and GSC 17 is disposed along RS 5between GSC 26 and GSC 20. GSC 19 is disposed along RS 6 between theextremity of the junction 38 and GSC 18; GSC 17 is disposed along RS 6between GSC 19 and GSC 27; GSC 27 is disposed along RS 6 between GSC 17and GSC 15; GSC 15 is disposed along RS 6 between GSC 27 and GSC 16; andGSC 16 is disposed along RS 6 between GSC 15 and GSC 28. GSC 32 isdisposed along RS 7 between the extremity of the junction 39 and GSC 27;GSC 27 is disposed along RS 7 between GSC 32 and GSC 26; GSC 26 isdisposed along RS 7 between GSC 27 and GSC 22; GSC 22 is disposed alongRS 7 between GSC 26 and GSC 23; GSC 23 is disposed along RS 7 betweenGSC 22 and GSC 33; GSC 33 is disposed along RS 7 between GSC 23 and GSC34; GSC 34 is disposed along RS 7 between GSC 33 and GSC 35; and GSC 35is disposed along RS 7 between GSC 34 and GSC 36. GSC 36 is disposedalong RS 8 between extremity of the junction 40 and GSC 24; GSC 24 isdisposed along RS 8 between GSC 36 and GSC 21; GSC 21 is disposed alongRS 8 between GSC 24 and GSC 25; GSC 25 is disposed along RS 8 betweenGSC 21 and GSC 28; GSC 28 is disposed along RS 8 between GSC 25 and GSC29; GSC 29 is disposed along RS 8 between GSC 28 and GSC 30; GSC 30 isdisposed along RS 8 between GSC 29 and GSC 31; and GSC 31 is disposedalong RS 8 between GSC 30 and GSC 32.

The above description of FIG. 1 applies also to FIG. 2. FIG. 2 is a planview schematic of the arrangement of roadways in a second embodiment ofthe invention. This embodiment has two loop ramps and requires as few astwo bridges. This embodiment is based on a horizontal reflection of thedrawing of FIG. 1.

FIG. 3 is a plan view schematic of the arrangement of roadways in athird embodiment of the invention. This embodiment has no loop ramps andrequires as few as three bridges.

RS 7 intersects with RS 6 at GSC 41; RS 7 intersects with RS 5 at GSC42; RS 7 intersects with RS 1 at GSC 43; RS 7 intersects with RS 2 atGSC 44; RS 7 intersects with RS 3 at GSC 45; and RS 7 intersects with RS4 at GSC 46. RS 8 intersects with RS 4 at GSC 47; RS 8 intersects withRS 3 at GSC 48; RS 8 intersects with RS 2 at GSC 49; RS 8 intersectswith RS 1 at GSC 50; RS 8 intersects with RS 5 at GSC 51; and RS 8intersects with RS 6 at GSC 52.

GSC 9 is disposed along RS 1 between extremity of the junction 37 andGSC 10; GSC 10 is disposed along RS 1 between GSC 9 and GSC 43; GSC 43is disposed along RS 1 between GSC 10 and GSC 50; GSC 50 is disposedalong RS 1 between GSC 43 and GSC 17; and GSC 17 is disposed along RS 1between GSC 50 and GSC 18. GSC 19 is disposed along RS 2 betweenextremity of the junction 38 and GSC 20; GSC 20 is disposed along RS 2between GSC 19 and GSC 49; GSC 49 is disposed along RS 2 between GSC 20and GSC 44; GSC 44 is disposed along RS 2 between GSC 44 and GSC 11; andGSC 11 is disposed along RS 2 between GSC 44 and GSC 12. GSC 13 isdisposed along RS 5 between extremity of the junction 37 and GSC 14; GSC14 is disposed along RS 5 between GSC 13 and GSC 42; GSC 42 is disposedalong RS 5 between GSC 14 and GSC 51; GSC 51 is disposed along RS 5between GSC 42 and GSC 17; and GSC 17 is disposed along RS 5 between GSC51 and GSC 20. GSC 19 is disposed along RS 6 between extremity of thejunction 38 and GSC 18; GSC 18 is disposed along RS 6 between GSC 19 andGSC 52; GSC 52 is disposed along RS 6 between GSC 18 and GSC 41; GSC 41is disposed along RS 6 between GSC 52 and GSC 15; and GSC 15 is disposedalong RS 6 between GSC 41 and GSC 16. GSC 41 is disposed along RS 7between extremity of the junction 39 and GSC 42; GSC 42 is disposedalong RS 7 between GSC 41 and GSC 43; GSC 43 is disposed along RS 7between GSC 42 and GSC 44; GSC 44 is disposed along RS 7 between GSC 43and GSC 45; and GSC 45 is disposed along RS 7 between GSC 44 and GSC 46.GSC 47 is disposed along RS 8 between extremity of the junction 40 andGSC 48; GSC 48 is disposed along RS 8 between GSC 47 and GSC 49; GSC 49is disposed along RS 8 between GSC 48 and GSC 50; GSC 50 is disposedalong RS 8 between GSC 49 and GSC 51; and GSC 51 is disposed along RS 8between GSC 50 and GSC 52.

The above description of FIG. 3 applies also to FIG. 4. FIG. 4 is a planview schematic of the arrangement of roadways in a fourth embodiment ofthe invention. This embodiment has no loop ramps and requires as few asthree bridges. This embodiment is based on a horizontal reflection ofthe drawing of FIG. 3.

FIG. 5 is a plan view schematic of the arrangement of roadways in afifth embodiment of the invention. This embodiment has no loop ramps andrequires as few as three bridges. U-turn ramps are also provided foreach leg of the interchange.

RS 7 intersects with RS 6 at GSC 41; RS 7 intersects with RS 5 at GSC42; RS 7 intersects with RS 1 at GSC 43; RS 7 intersects with RS 2 atGSC 44; RS 7 intersects with RS 3 at GSC 45; and RS 7 intersects with RS4 at GSC 46. RS 8 intersects with RS 4 at GSC 47; RS 8 intersects withRS 3 at GSC 48; RS 8 intersects with RS 2 at GSC 49, RS 8 intersectswith RS 1 at GSC 50; RS 8 intersects with RS 5 at GSC 51; and RS 8intersects with RS 6 at GSC 52.

RSs 53, 54, 55, and 56 are commonly called U-turn ramps. RS 53 isprovided for U-turn traffic traveling from the extremity of the junction37 and returning to the extremity of the junction 37. RS 54 is providedfor U-turn traffic traveling from the extremity of the junction 38 andreturning to the extremity of the junction 38. RS 55 is provided forU-turn traffic traveling from the extremity of the junction 39 andreturning to the extremity of the junction 39. RS 56 is provided forU-turn traffic traveling from the extremity of the junction 40 andreturning to the extremity of the junction 40.

RS 53 intersects with RS 55 at GSC 57; RS 53 intersects with RS 4 at GSC58; RS 53 intersects with RS 3 at GSC 59; RS 53 intersects with RS 55 atGSC 60; RS 53 intersects with RS 7 at GSC 61; RS 53 intersects with RS 8at GSC 62; RS 53 intersects with RS 1 at GSC 63; RS 53 intersects withRS 2 at GSC 64; RS 53 intersects with RS 8 at GSC 65; RS 53 intersectswith RS 7 at GSC 66; RS 53 intersects with RS 55 at GSC 67; RS 53intersects with RS 3 at GSC 68; RS 53 intersects with RS 4 at GSC 69;and RS 53 intersects with RS 55 at GSC 70. RS 54 intersects with RS 2 atGSC 71; and RS 54 intersects with RS 1 at GSC 72. RS 55 intersects withRS 6 at GSC 73; RS 55 intersects with RS 5 at GSC 74; RS 55 intersectswith RS 1 at GSC 75; RS 55 intersects with RS 2 at GSC 76; RS 55intersects with RS 3 at GSC 77; RS 55 intersects with RS 4 at GSC 78; RS55 intersects with RS 2 at GSC 79; RS 55 intersects with RS 1 at GSC 80;RS 55 intersects with RS 5 at GSC 81; and RS 55 intersects with RS 6 atGSC 82. RS 56 intersects with RS 4 at GSC 83; and RS 56 intersects withRS 3 at GSC 84.

GSC 80 is disposed along RS 1 between extremity of the junction 37 andGSC 9; GSC 9 is disposed along RS 1 between GSC 80 and GSC 10; GSC 10 isdisposed along RS 1 between GSC 9 and GSC 75; GSC 75 is disposed alongRS 1 between GSC 10 and GSC 62; GSC 62 is disposed along RS 1 betweenGSC 75 and GSC 50; GSC 50 is disposed along RS 1 between GSC 62 and GSC63; GSC 63 is disposed along RS 1 between GSC 50 and GSC 17; and GSC 17is disposed along RS 1 between GSC 63 and GSC 18. GSC 71 is disposedalong RS 2 between extremity of the junction 38 and GSC 19; GSC 19 isdisposed along RS 2 between GSC 71 and GSC 20; GSC 20 is disposed alongRS 2 between GSC 19 and GSC 64; GSC 64 is disposed along RS 2 betweenGSC 20 and GSC 49; GSC 49 is disposed along RS 2 between GSC 64 and GSC44; GSC 44 is disposed along RS 2 between GSC 49 and GSC 76; GSC 76 isdisposed along RS 2 between GSC 44 and GSC 11; GSC 11 is disposed alongRS 2 between GSC 76 and GSC 12; and GSC 12 is disposed along RS 2between GSC 11 and GSC 79. GSC 15 is disposed along RS 3 betweenextremity of the junction 39 and GSC 14; GSC 14 is disposed along RS 3between GSC 15 and GSC 59; GSC 59 is disposed along RS 3 between GSC 14and GSC 10; GSC 10 is disposed along RS 3 between GSC 59 and GSC 11; GSC11 is disposed along RS 3 between GSC 10 and GSC 68; GSC 68 is disposedalong RS 3 between GSC 11 and GSC 77; GSC 77 is disposed along RS 3between GSC 68 and GSC 45; GSC 45 is disposed along RS 3 between GSC 77and GSC 48; and GSC 48 is disposed along RS 3 between GSC 45 and GSC 84.GSC 83 is disposed along RS 4 between extremity of the junction 40 andGSC 47; GSC 47 is disposed along RS 4 between GSC 83 and GSC 46; GSC 46is disposed along RS 4 between GSC 47 and GSC 78; GSC 78 is disposedalong RS 4 between GSC 46 and GSC 69; GSC 69 is disposed along RS 4between GSC 78 and GSC 12; GSC 12 is disposed along RS 4 between GSC 69and GSC 9; GSC 9 is disposed along RS 4 between GSC 12 and GSC 58; GSC58 is disposed along RS 4 between GSC 9 and GSC 13; and GSC 13 isdisposed along RS 4 between GSC 58 and GSC 16. GSC 41 is disposed alongRS 7 between extremity of the junction 39 and GSC 42; GSC 42 is disposedalong RS 7 between GSC 41 and GSC 61; GSC 61 is disposed along RS 7between GSC 42 and GSC 43; GSC 43 is disposed along RS 7 between GSC 61and GSC 44; GSC 44 is disposed along RS 7 between

GSC 43 and GSC 66; GSC 66 is disposed along RS 7 between GSC 44 and GSC45; and GSC 45 is disposed along RS 7 between GSC 66 and GSC 46. GSC 47is disposed along RS 8 between extremity of the junction 40 and GSC 48;GSC 48 is disposed along RS 8 between GSC 47 and GSC 65; GSC 65 isdisposed along RS 8 between GSC 48 and GSC 49; GSC 49 is disposed alongRS 8 between GSC 65 and GSC 50; GSC 50 is disposed along between GSC 49and GSC 62; GSC 62 is disposed along RS 8 between GSC 50 and GSC 51; andGSC 51 is disposed along RS 8 between GSC 62 and GSC 52.

The above description of FIG. 5 applies also to FIG. 6. FIG. 6 is a planview schematic of the arrangement of roadways in a sixth embodiment ofthe invention. This embodiment has no loop ramps and requires as few asthree bridges. U-turn ramps are also provided for each leg of theinterchange. This embodiment is based on a horizontal reflection of thedrawing of FIG. 5.

FIG. 7 is a plan view schematic of the arrangement of roadways in aseventh embodiment of the invention. This embodiment has one loop rampand requires as few as three bridges.

RS 1 intersects with RS 8 at GSC 21; RS 1 intersects with RS 7 at GSC22; RS 2 intersects with RS 7 at GSC 23; RS 2 intersects with RS 8 GSC24; RS 5 intersects with RS 8 at GSC 25; RS 5 intersects with RS 7 atGSC 26; RS 6 intersects with RS 7 at GSC 27; RS 6 intersects with RS 8at GSC 28; RS 8 intersects with RS 8 at GSC 29; RS 8 intersects with RS4 at GSC 30; RS 8 intersects with RS 3 at GSC 31; RS 8 intersects withRS 7 at GSC 32; RS 7 intersects with RS 3 at GSC 94; RS 7 intersectswith RS 4 at GSC 95; and RS 7 intersects with RS 8 at GSC 96.

GSC 21 is disposed along RS 1 between the extremity of the junction 37and GSC 9; GSC 9 is disposed along RS 1 between GSC 21 and GSC 10; GSC10 is disposed along RS 1 between GSC 9 and GSC 22; GSC 22 is disposedalong RS 1 between GSC 10 and GSC 17; and GSC 17 is disposed along RS 1between GSC 22 and GSC 18. GSC 19 is disposed along RS 2 between theextremity of the junction 38 and GSC 20; GSC 20 is disposed along RS 2between GSC 19 and GSC 23; GSC 23 is disposed along RS 2 between GSC 11and GSC 20; GSC 11 is disposed along RS 2 between GSC 23 and GSC 12; andGSC 12 is disposed along RS 2 between GSC 11 and GSC 24. GSC 25 isdisposed along RS 5 between the extremity of the junction 37 and GSC 13;GSC 13 is disposed along RS 5 between GSC 25 and GSC 14; GSC 14 isdisposed along RS 5 between GSC 13 and GSC 26; GSC 26 is disposed alongRS 5 between GSC 14 and GSC 17; and GSC 17 is disposed along RS 5between GSC 26 and GSC 20. GSC 19 is disposed along RS 6 between theextremity of the junction 38 and GSC 18; GSC 17 is disposed along RS 6between GSC 19 and GSC 27; GSC 27 is disposed along RS 6 between GSC 17and GSC 15; GSC 15 is disposed along RS 6 between GSC 27 and GSC 16; andGSC 16 is disposed along RS 6 between GSC 15 and GSC 28. GSC 32 isdisposed along RS 7 between the extremity of the junction 39 and GSC 27;GSC 27 is disposed along RS 7 between GSC 32 and GSC 26; GSC 26 isdisposed along RS 7 between GSC 27 and GSC 22; GSC 22 is disposed alongRS 7 between GSC 26 and GSC 23; GSC 23 is disposed along RS 7 betweenGSC 22 and GSC 85; GSC 85 is disposed along RS 7 between GSC 23 and GSC86; and GSC 86 is disposed along RS 7 between GSC 85 and GSC 87. GSC 87is disposed along RS 8 between extremity of the junction 40 and GSC 24;GSC 24 is disposed along RS 8 between GSC 87 and GSC 21; GSC 21 isdisposed along RS 8 between GSC 24 and GSC 25; GSC 25 is disposed alongRS 8 between GSC 21 and GSC 28; GSC 28 is disposed along RS 8 betweenGSC 25 and GSC 29; GSC 29 is disposed along RS 8 between GSC 28 and GSC30; GSC 30 is disposed along RS 8 between GSC 29 and GSC 31; and GSC 31is disposed along RS 8 between GSC 30 and GSC 32.

The above description of FIG. 7 applies also to FIG. 8. FIG. 8 is a planview schematic of the arrangement of roadways in an eighth embodiment ofthe invention. This embodiment has one loop ramp and requires as few asthree bridges. This embodiment is based on a horizontal reflection ofthe drawing of FIG. 7.

FIG. 9 is a plan view schematic of the arrangement of roadways in aninth embodiment of the invention. This embodiment has one loop ramp andrequires as few as three bridges.

RS 1 intersects with RS 8 at GSC 21; RS 1 intersects with RS 7 at GSC92; RS 2 intersects with RS 7 at GSC 92; RS 2 intersects with RS 8 GSC24; RS 5 intersects with RS 8 at GSC 25; RS 5 intersects with RS 7 atGSC 90; RS 6 intersects with RS 7 at GSC 89; RS 6 intersects with RS 8at GSC 97; RS 8 intersects with RS 4 at GSC 98; RS 8 intersects with RS3 at GSC 99; RS 8 intersects with RS 7 at GSC 88; RS 7 intersects withRS 3 at GSC 94; RS 7 intersects with RS 4 at GSC 95; and RS 7 intersectswith RS 8 at GSC 96.

GSC 21 is disposed along RS 1 between the extremity of the junction 37and GSC 9; GSC 9 is disposed along RS 1 between GSC 21 and GSC 10; GSC10 is disposed along RS 1 between GSC 9 and GSC 91; GSC 91 is disposedalong RS 1 between GSC 10 and GSC 17; and GSC 17 is disposed along RS 1between GSC 91 and GSC 18. GSC 19 is disposed along RS 2 between theextremity of the junction 38 and GSC 20; GSC 20 is disposed along RS 2between GSC 19 and GSC 92; GSC 92 is disposed along RS 2 between GSC 11and GSC 20; GSC 11 is disposed along RS 2 between GSC 92 and GSC 12; andGSC 12 is disposed along RS 2 between GSC 11 and GSC 24. GSC 25 isdisposed along RS 5 between the extremity of the junction 37 and GSC 13;GSC 13 is disposed along RS 5 between GSC 25 and GSC 14; GSC 14 isdisposed along RS 5 between GSC 13 and GSC 90; GSC 90 is disposed alongRS 5 between GSC 14 and GSC 17; and GSC 17 is disposed along RS 5between GSC 26 and GSC 20. GSC 19 is disposed along RS 6 between theextremity of the junction 38 and GSC 18; GSC 17 is disposed along RS 6between GSC 19 and GSC 89; GSC 89 is disposed along RS 6 between GSC 17and GSC 15; GSC 15 is disposed along RS 6 between GSC 89 and GSC 16; andGSC 16 is disposed along RS 6 between GSC 15 and GSC 97. GSC 88 isdisposed along RS 7 between the extremity of the junction 39 and GSC 89;GSC 89 is disposed along RS 7 between GSC 90 and GSC 89; GSC 90 isdisposed along RS 7 between GSC 89 and GSC 91; GSC 91 is disposed alongRS 7 between GSC 90 and GSC 92; GSC 92 is disposed along RS 7 betweenGSC 91 and GSC 93; GSC 93 is disposed along RS 7 between GSC 92 and GSC94; GSC 94 is disposed along RS 7 between GSC 93 and GSC 95; and GSC 95is disposed along RS 7 between GSC 94 and GSC 96. GSC 96 is disposedalong RS 8 between extremity of the junction 40 and GSC 24; GSC 24 isdisposed along RS 8 between GSC 87 and GSC 21; GSC 21 is disposed alongRS 8 between GSC 24 and GSC 25; GSC 25 is disposed along RS 8 betweenGSC 21 and GSC 97; GSC 97 is disposed along RS 8 between GSC 25 and GSC98; GSC 98 is disposed along RS 8 between GSC 97 and GSC 99; and GSC 99is disposed along RS 8 between GSC 98 and GSC 88.

The above description of FIG. 9 applies also to FIG. 10. FIG. 10 is aplan view schematic of the arrangement of roadways in a tenth embodimentof the invention. This embodiment has one loop ramp and requires as fewas three bridges. This embodiment is based on a horizontal reflection ofthe drawing of FIG. 9.

FIG. 11 is a plan view schematic of the arrangement of roadways in aneleventh embodiment of the invention. This embodiment has no loop rampsand requires as few as four bridges.

RS 7 intersects with RS 6 at GSC 41; RS 7 intersects with RS 5 at GSC42; RS 7 intersects with RS 1 at GSC 43; RS 7 intersects with RS 2 atGSC 44; RS 7 intersects with RS 3 at GSC 85; and RS 7 intersects with RS4 at GSC 86; and RS 7 intersects with RS 8 at GSC 87. RS 8 intersectswith RS 6 at GSC 97; RS 8 intersects with RS 2 at GSC 24; RS 8intersects with RS 1 at GSC 21; RS 8 intersects with RS 5 at GSC 25; RS8 intersects with RS 6 at GSC 97; RS 8 intersects with RS 4 at GSC 98;RS 8 intersects with RS 3 at GSC 99; and RS 8 intersects with RS 7 atGSC 88.

GSC 21 is disposed along RS 1 between extremity of the junction 37 andGSC 9; GSC 9 is disposed along RS 1 between GSC 21 and GSC 10; GSC 10 isdisposed along RS 1 between GSC 9 and GSC 43; GSC 43 is disposed alongRS 1 between GSC 10 and GSC 17; and GSC 17 is disposed along RS 1between GSC 50 and GSC 18. GSC 19 is disposed along RS 2 betweenextremity of the junction 38 and GSC 20; GSC 20 is disposed along RS 2between GSC 19 and GSC 49; GSC 49 is disposed along RS 2 between GSC 20and GSC 44; GSC 44 is disposed along RS 2 between GSC 44 and GSC 11; GSC11 is disposed along RS 2 between GSC 44 and GSC 12; and GSC 12 isdisposed along RS 2 between GSC 11 and GSC 24. GSC 25 is disposed alongRS 5 between extremity of the junction 37 and GSC 13; GSC 13 is disposedalong RS 5 between GSC 25 and GSC 14; GSC 14 is disposed along RS 5between GSC 13 and GSC 42; GSC 42 is disposed along RS 5 between GSC 14and GSC 17; and GSC 17 is disposed along RS 5 between GSC 42 and GSC 20.GSC 19 is disposed along RS 6 between extremity of the junction 38 andGSC 18; GSC 18 is disposed along RS 6 between GSC 19 and GSC 41; GSC 41is disposed along RS 6 between GSC 52 and GSC 15; GSC 15 is disposedalong RS 6 between GSC 41 and GSC 16; and GSC 16 is disposed along RS 6between

GSC 15 and GSC 97. GSC 88 is disposed along RS 7 between extremity ofthe junction 39 and GSC 41; GSC 41 is disposed along RS 7 between GSC 88and GSC 42; GSC 42 is disposed along RS 7 between GSC 41 and GSC 43; GSC43 is disposed along RS 7 between GSC 42 and GSC 44; GSC 44 is disposedalong RS 7 between GSC 43 and GSC 85; GSC 85 is disposed along RS 7between GSC 44 and GSC 86; and GSC 86 is disposed along RS 7 between GSC85 and GSC 87. GSC 87 is disposed along RS 8 between extremity of thejunction 40 and GSC 24; GSC 24 is disposed along RS 8 between GSC 87 andGSC 21; GSC 21 is disposed along RS 8 between GSC 24 and GSC 25; GSC 25is disposed along RS 8 between GSC 21 and GSC 97; GSC 97 is disposedalong RS 8 between GSC 21 and GSC 98; GSC 98 is disposed along RS 8between GSC 97 and GSC 99; and GSC 99 is disposed along RS 8 between GSC98 and GSC 88.

The above description of FIG. 11 applies also to FIG. 12. FIG. 12 is aplan view schematic of the arrangement of roadways in a twelfthembodiment of the invention. This embodiment has no loop ramps andrequires as few as four bridges. This embodiment is based on ahorizontal reflection of the drawing of FIG. 11.

Regarding all of the embodiments shown in FIGS. 13 to 30, it will beobvious to a practitioner with ordinary skill in the art of geometricdesign of roadways how to design an appropriate geometry which usesadditional bridges if the particular requirements of a given siterequire such a geometry. For example, where a freeway has a very widemedian, it may be more appropriate to place the freeway on at least twobridges rather than one very wide bridge. It will also be obvious tosuch a practitioner how to modify the arrangements of overpasses andunderpasses so a particular group of RSs is placed on an overpass ratherthan an underpass, for example. It will also be obvious to a person ofordinary skill that each of the embodiments may be constructed witharrangements of overpasses and underpasses different from those shown inthe drawings. For example, where a first RS is shown as extendingunderneath other RSs, it is also possible to instead extend the first RSover the other RSs. In addition, it will be obvious to a person ofordinary skill that adjacent RSs in the embodiments may be connected toeach other, or may be separated, and may have any vertical alignment,horizontal alignment, or cross-sectional characteristics desired. Forexample, RS 3 may adjoin RS 4, and the boundary between the two RSs maysimply be marked with painted lines, or alternatively, RS 3 may beseparated from RS 4 by a wide grassy median; and RS 3 may have a curvinghorizontal or vertical alignment if required; and RS 3 may have onetravel lane or several travel lanes.

It will also be obvious to a practitioner with ordinary skill in the artof geometric design of roadways how to interpret FIGS. 13 to 30. Inorder to minimize clutter in these drawings, so-called ‘hidden lines’have not been drawn. A practitioner with ordinary skill willnevertheless understand, for example, that in the embodiment of FIG. 13,RS 3 extends continuously from the extremity of the junction 39 to theextremity of the junction 40. Though the drawn lines representing theouter edges of RS 3 do not intersect the drawn lines representing theedges of RSs 8, 6, 5, 1, 2, and 7, it will be obvious to a person ofordinary skill that RS 3 continues underneath RSs 8, 6, 5, 1, 2, and 7.

FIG. 13 shows a possible arrangement of overpasses and underpasses forthe first embodiment of the invention. Arrows show the direction oftraffic flow along the different RSs in the interchange (assumingright-hand traffic). In this figure, right-turn ramps are shown. Theseare RSs 100 through 103. RS 100 is provided for traffic moving from theextremity of the junction 37 to the extremity of the junction 39. RS 101is provided for traffic moving from the extremity of the junction 38 tothe extremity of the junction 40. RS 102 is provided for traffic movingfrom the extremity of the junction 39 to the extremity of the junction38. RS 103 is provided for traffic moving from the extremity of thejunction 40 to the extremity of the junction 37. The foregoingdescription of RSs 100 through 103 also applies to FIGS. 14 through 30.In the version of the embodiment shown, two bridges are required, afirst bridge 104 and a second bridge 105. Other arrangements ofoverpasses and underpasses are also possible; for example, RSs 8 (whereit is laterally adjacent to RS 1), 1, 2, 5, 6, and 7 (where it islaterally adjacent to RS 2) can pass underneath RSs 8 (where it islaterally adjacent to RS 4), 4, 3, and 7 (where it is laterally adjacentto RS 3). In addition, if the particular constraints of a real-worldsite require it, the embodiment can be constructed with more than twobridges. (See FIG. 25 for one such example.) The above description ofFIG. 13 applies also to FIG. 14, except that FIG. 14 shows a possiblearrangement of overpasses and underpasses for the second embodiment ofthe invention.

FIG. 15 shows a possible arrangement of overpasses and underpasses forthe third embodiment of the invention. Arrows show the direction oftraffic flow along the different RSs in the interchange (assumingright-hand traffic). hi the version of the embodiment shown, threebridges are required, a first bridge 104, a second bridge 106, and athird bridge 107. Other arrangements of overpasses and underpasses arealso possible. In addition, if the particular constraints of areal-world site require it, the embodiment can be constructed with morethan three bridges. (See FIG. 27 for one such example.) The abovedescription of FIG. 15 applies also to FIG. 16, except that FIG. 15shows a possible arrangement of overpasses and underpasses for thefourth embodiment of the invention. FIG. 17 shows a possible arrangementof overpasses and underpasses for the fifth embodiment of the invention.Arrows show the direction of traffic flow along the different RSs in theinterchange (assuming right-hand traffic). In the version of theembodiment shown, three bridges are required, a first bridge 104, asecond bridge 106, and a third bridge 107. Other arrangements ofoverpasses and underpasses are also possible. In addition, if theparticular constraints of a real-world site require it, the embodimentcan be constructed with more than three bridges. As mentionedpreviously, one or more roadways may be omitted from any of theembodiments of this invention. In particular, when constructing thefifth embodiment, it may be preferred to omit one or more of the U-turnramps. The above description of FIG. 17 applies also to FIG. 18, exceptthat FIG. 18 shows a possible arrangement of overpasses and underpassesfor the sixth embodiment of the invention.

FIG. 19 shows a possible arrangement of overpasses and underpasses forthe seventh embodiment of the invention. hi the version of theembodiment shown, three bridges are required, a first bridge 104, asecond bridge 105, and a third bridge 107. Other arrangements ofoverpasses and underpasses are also possible. In addition, if theparticular constraints of a real-world site require it, the embodimentcan be constructed with more than three bridges. The above descriptionof FIG. 19 applies also to FIG. 20, except that FIG. 20 shows a possiblearrangement of overpasses and underpasses for the eighth embodiment ofthe invention.

FIG. 21 shows a possible arrangement of overpasses and underpasses forthe ninth embodiment of the invention. In the version of the embodimentshown, three bridges are required, a first bridge 104, a second bridge105, and a third bridge 108. Other arrangements of overpasses andunderpasses are also possible. In addition, if the particularconstraints of a real-world site require it, the embodiment can beconstructed with more than three bridges. The above description of FIG.21 applies also to FIG. 22, except that FIG. 22 shows a possiblearrangement of overpasses and underpasses for the tenth embodiment ofthe invention.

FIG. 23 shows a possible arrangement of overpasses and underpasses forthe eleventh embodiment of the invention. In the version of theembodiment shown, four bridges are required, a first bridge 104, asecond bridge 106, a third bridge 107, and a fourth bridge 108. Otherarrangements of overpasses and underpasses are also possible. Inaddition, if the particular constraints of a real-world site require it,the embodiment can be constructed with more than three bridges. Theabove description of FIG. 23 applies also to FIG. 24, except that FIG.24 shows a possible arrangement of overpasses and underpasses for thetwelfth embodiment of the invention.

FIG. 25 shows another possible arrangement of overpasses and underpassesfor the first embodiment of the invention. In the version of theembodiment shown, three bridges are required, a first bridge 104, asecond bridge 105, and a third bridge 110. Other arrangements ofoverpasses and underpasses are also possible. In addition, if theparticular constraints of a real-world site require it, the embodimentcan be constructed with more than three bridges. The above descriptionof FIG. 25 applies also to FIG. 26, except that FIG. 26 shows a possiblearrangement of overpasses and underpasses for the second embodiment ofthe invention.

FIG. 27 shows another possible arrangement of overpasses and underpassesfor the third embodiment of the invention. FIG. 27 shows an exceptionalexample of how the third embodiment can be constructed using more thanthree bridges if desired. In the version of the embodiment shown, elevenbridges are required: a first bridge 104, a second bridge 106, a thirdbridge 107, a fourth bridge 110, a fifth bridge 111, a sixth bridge 112,a seventh bridge 113, an eighth bridge 114, a ninth bridge 115, a tenthbridge 116, and an eleventh bridge 117. Other arrangements of overpassesand underpasses are also possible. In addition, if the particularconstraints of a real-world site require it, the embodiment can beconstructed with more bridges. The above description of FIG. 27 appliesalso to FIG. 28, except that FIG. 28 shows a possible arrangement ofoverpasses and underpasses for the fourth embodiment of the invention.

FIG. 29 shows another possible arrangement of overpasses, underpasses,and right-turn ramps for the third embodiment of the invention. Thisembodiment is similar to that shown in FIG. 15; however, the right-turnramps 101 and 103 are arranged differently in FIG. 29. The exit forright-turn ramp 101 is located on the left-hand side (from the point ofview of traffic approaching the exit) of the exit for left-turn ramp 6;similarly, the exit for right-turn ramp 103 is located on the left-handside (from the point of view of traffic approaching the exit) of theexit for left-turn ramp 8. The entrance to the freeway from right-turnramp 101 is located on the left-hand side (from the point of view oftraffic entering the freeway) of the entrance for left-turn ramp 5;similarly, the entrance to the freeway from right-turn ramp 103 islocated on the left-hand side (from the point of view of trafficentering the freeway) of the entrance for left-turn ramp 7. As notedabove, it will be obvious to a practitioner with ordinary skill in theart of geometric design of roadways how best to add right-turn ramps toany embodiment of the present invention. FIGS. 29 and 30 are providedsimply to show possible arrangements where the right-turn exits on twoapproaches to the junction are located to the left of the left-turnexits, from the perspective of a driver approaching the exits. A similararrangement of right turn ramps is seen in the turbine interchange ofBelgian Pat. No. 638,746 and No. 641,129. The above description of FIG.29 applies also to FIG. 30, except that FIG. 30 shows a possiblearrangement of overpasses and underpasses for the fourth embodiment ofthe invention.

It will be obvious to those skilled in the art of geometric design ofroadways how to modify the embodiments of this invention by replacingone or more of the left-turn ramps with one or more left-turn ramps ofdifferent arrangements. Such ramps are often called flyover ramps, andare often given forms similar to the left-turn ramps of the ‘turbine’ orfour-level directional interchange configurations mentioned above. Suchmodifications are commonly made when it becomes necessary to increasethe capacity of an interchange.

It will be obvious to those skilled in the art of transportationengineering that the configurations of road surfaces in the embodimentsof this invention may also be applied to various kinds of traveled waysor lines of transportation. For example, the road surfaces of theembodiments described herein may be railroads, bicycle paths, footpaths,and so forth.

Those of ordinary skill will understand and appreciate the existence ofother variations, combinations, and equivalents of the specificembodiments and examples herein. The invention should therefore not belimited by the above described embodiments and examples, but by allembodiments and methods within the scope and spirit of the invention.

What is claimed is:
 1. A road junction comprising: a first road surfacefor traffic traveling in a first direction; a second road surface fortraffic traveling in a direction substantially opposite to said firstdirection; a third road surface for traffic traveling in a directionintersecting said first and second road surfaces; a fourth road surfacefor traffic traveling in a direction substantially opposite to saidtraffic traveling on said third road surface; a first, a second, athird, and a fourth extremity of the junction; said first road surfaceextending from said first extremity of the junction to said secondextremity of the junction; said second road surface extending from saidsecond extremity of the junction to said first extremity of thejunction; said third road surface extending from said third extremity ofthe junction to said fourth extremity of the junction; said fourth roadsurface extending from said fourth extremity of the junction to saidthird extremity of the junction; a fifth road surface extending fromsaid first extremity of the junction to said fourth extremity of thejunction; a sixth road surface extending from said second extremity ofthe junction to said third extremity of the junction; at said firstextremity of the junction, said first road surface being disposedlaterally between said second and fifth road surfaces; at said secondextremity of the junction, said second road surface being disposedlaterally between said first and sixth road surfaces; at said thirdextremity of the junction, said fourth road surface being disposedlaterally between said sixth and third road surfaces; at said fourthextremity of the junction, said third road surface being disposedlaterally between said fifth and fourth road surfaces; said first roadsurface intersecting said fourth road surface at a first grade-separatedcrossing; said first road surface intersecting said third road surfaceat a second grade-separated crossing; said second road surfaceintersecting said third road surface at a third grade-separatedcrossing; said second road surface intersecting said fourth road surfaceat a fourth grade-separated crossing; said fifth road surfaceintersecting said fourth road surface at a fifth grade-separatedcrossing; said fifth road surface intersecting said third road surfaceat a sixth grade-separated crossing; said sixth road surfaceintersecting said third road surface at a seventh grade-separatedcrossing; said sixth road surface intersecting said fourth road surfaceat an eighth grade-separated crossing; said fifth road surfaceintersecting said first road surface at a ninth grade-separatedcrossing; said fifth road surface intersecting said second road surfaceat a twelfth grade-separated crossing; said sixth road surfaceintersecting said second road surface at an eleventh grade-separatedcrossing; said sixth road surface intersecting said first road surfaceat a tenth grade-separated crossing; said first grade-separated crossingbeing disposed intermediately along the traveled length of said firstroad surface between said first extremity of the junction and saidsecond grade-separated crossing; said second grade-separated crossingbeing disposed intermediately along the traveled length of said firstroad surface between said first grade-separated crossing and said ninthgrade-separated crossing; said ninth grade-separated crossing beingdisposed intermediately along the traveled length of said first roadsurface between said second grade-separated crossing and said tenthgrade-separated crossing; said eleventh grade-separated crossing beingdisposed intermediately along the traveled length of said second roadsurface between said second extremity of the junction and said twelfthgrade-separated crossing; said twelfth grade-separated crossing beingdisposed intermediately along the traveled length of said second roadsurface between said eleventh grade-separated crossing and said thirdgrade-separated crossing; said third grade-separated crossing beingdisposed intermediately along the traveled length of said second roadsurface between said twelfth grade-separated crossing and said fourthgrade-separated crossing; said fifth grade-separated crossing beingdisposed intermediately along the traveled length of said fifth roadsurface between said first extremity of the junction and said sixthgrade-separated crossing; said sixth grade-separated crossing beingdisposed intermediately along the traveled length of said fifth roadsurface between said fifth grade-separated crossing and said ninthgrade-separated crossing; said ninth grade-separated crossing beingdisposed intermediately along the traveled length of said fifth roadsurface between said sixth grade-separated crossing and said twelfthgrade-separated crossing; said eleventh grade-separated crossing beingdisposed intermediately along the traveled length of said sixth roadsurface between said second extremity of the junction and said tenthgrade-separated crossing; said tenth grade-separated crossing beingdisposed intermediately along the traveled length of said sixth roadsurface between said eleventh grade-separated crossing and said seventhgrade-separated crossing; and said seventh grade-separated crossingbeing disposed intermediately along the traveled length of said sixthroad surface between said tenth grade-separated crossing and said eighthgrade-separated crossing.
 2. The road junction of claim 1, furthercomprising: a seventh road surface extending from said third extremityof the junction to said first extremity of the junction; an eighth roadsurface extending from said fourth extremity of the junction to saidsecond extremity of the junction; at said first extremity of thejunction, said second road surface being disposed laterally between saidseventh and first road surfaces; at said third extremity of thejunction, said third road surface being disposed laterally between saidfourth and seventh road surfaces; at said fourth extremity of thejunction, said fourth road surface being disposed laterally between saidthird and eighth road surfaces; at said second extremity of thejunction, said first road surface being disposed laterally between saidsecond and eighth road surfaces; said first road surface intersectingsaid eighth road surface at a thirteenth grade-separated crossing; saidfirst road surface intersecting said seventh road surface at afourteenth grade-separated crossing; said second road surfaceintersecting said seventh road surface at a fifteenth grade-separatedcrossing; said second road surface intersecting said eighth road surfaceat a sixteenth grade-separated crossing; said fifth road surfaceintersecting said eighth road surface at a seventeenth grade-separatedcrossing; said fifth road surface intersecting said seventh road surfaceat an eighteenth grade-separated crossing; said sixth road surfaceintersecting said seventh road surface at a nineteenth grade-separatedcrossing; said sixth road surface intersecting said eighth road surfaceat a twentieth grade-separated crossing; said eighth road surfaceintersecting said eighth road surface at a twenty-first grade-separatedcrossing; said eighth road surface intersecting said fourth road surfaceat a twenty-second grade-separated crossing; said eighth road surfaceintersecting said third road surface at a twenty-third grade-separatedcrossing; said eighth road surface intersecting said seventh roadsurface at a twenty-fourth grade-separated crossing; said seventh roadsurface intersecting said seventh road surface at a twenty-fifthgrade-separated crossing; said seventh road surface intersecting saidthird road surface at a twenty-sixth grade-separated crossing; saidseventh road surface intersecting said fourth road surface at atwenty-seventh grade-separated crossing; said seventh road surfaceintersecting said eighth road surface at a twenty-eighth grade-separatedcrossing; said thirteenth grade-separated crossing being disposedintermediately along the traveled length of said first road surfacebetween said first extremity of the junction and said firstgrade-separated crossing; said fourteenth grade-separated crossing beingdisposed intermediately along the traveled length of said first roadsurface between said second grade-separated crossing and said ninthgrade-separated crossing; said fifteenth grade-separated crossing beingdisposed intermediately along the traveled length of said second roadsurface between said twelfth grade-separated crossing and said thirdgrade-separated crossing; said sixteenth grade-separated crossing beingdisposed intermediately along the traveled length of said second roadsurface between said fourth grade-separated crossing and said firstextremity of the junction; said seventeenth grade-separated crossingbeing disposed intermediately along the traveled length of said fifthroad surface between said first extremity of the junction and said fifthgrade-separated crossing; said eighteenth grade-separated crossing beingdisposed intermediately along the traveled length of said fifth roadsurface between said sixth grade-separated crossing and said ninthgrade-separated crossing; said nineteenth grade-separated crossing beingdisposed intermediately along the traveled length of said sixth roadsurface between said tenth grade-separated crossing and said seventhgrade-separated crossing; said eighth grade-separated crossing beingdisposed intermediately along the traveled length of said sixth roadsurface between said seventh grade-separated crossing and said twentiethgrade-separated crossing; said twenty-first grade-separated crossingbeing disposed intermediately along the traveled length of said eighthroad surface between said twentieth grade-separated crossing and saidtwenty-second grade-separated crossing; said twenty-secondgrade-separated crossing being disposed intermediately along thetraveled length of said eighth road surface between said twenty-firstgrade-separated crossing and said twenty-third grade-separated crossing;said twenty-third grade-separated crossing being disposed intermediatelyalong the traveled length of said eighth road surface between saidtwenty-second grade-separated crossing and said twenty-fourthgrade-separated crossing; said twenty-fifth grade-separated crossingbeing disposed intermediately along the traveled length of said seventhroad surface between said fifteenth grade-separated crossing and saidtwenty-sixth grade-separated crossing; said twenty-sixth grade-separatedcrossing being disposed intermediately along the traveled length of saidseventh road surface between said twenty-fifth grade-separated crossingand said twenty-seventh grade-separated crossing; and saidtwenty-seventh grade-separated crossing being disposed intermediatelyalong the traveled length of said seventh road surface between saidtwenty-sixth grade-separated crossing and said twenty-eighthgrade-separated crossing.
 3. The road junction of claim 1, furthercomprising: a seventh road surface extending from said third extremityof the junction to said first extremity of the junction; an eighth roadsurface extending from said fourth extremity of the junction to saidsecond extremity of the junction; at said first extremity of thejunction, said second road surface being disposed laterally between saidseventh and first road surfaces; at said third extremity of thejunction, said third road surface being disposed laterally between saidfourth and seventh road surfaces; at said fourth extremity of thejunction, said fourth road surface being disposed laterally between saidthird and eighth road surfaces; at said second extremity of thejunction, said first road surface being disposed laterally between saidsecond and eighth road surfaces; said first road surface intersectingsaid seventh road surface at a thirteenth grade-separated crossing; saidfirst road surface intersecting said eighth road surface at a fourteenthgrade-separated crossing; said second road surface intersecting saideighth road surface at a fifteenth grade-separated crossing; said secondroad surface intersecting said seventh road surface at a sixteenthgrade-separated crossing; said fifth road surface intersecting saidseventh road surface at a seventeenth grade-separated crossing; saidfifth road surface intersecting said eighth road surface at aneighteenth grade-separated crossing; said sixth road surfaceintersecting said eighth road surface at a nineteenth grade-separatedcrossing; said sixth road surface intersecting said seventh road surfaceat a twentieth grade-separated crossing; said seventh road surfaceintersecting said third road surface at a twenty-first grade-separatedcrossing; said seventh road surface intersecting said fourth roadsurface at a twenty-second grade-separated crossing; said eighth roadsurface intersecting said fourth road surface at a twenty-thirdgrade-separated crossing; said eighth road surface intersecting saidthird road surface at a twenty-fourth grade-separated crossing; saidthirteenth grade-separated crossing being disposed intermediately alongthe traveled length of said first road surface between said secondgrade-separated crossing and said fourteenth grade-separated crossing;said fourteenth grade-separated crossing being disposed intermediatelyalong the traveled length of said first road surface between saidthirteenth grade-separated crossing and said ninth grade-separatedcrossing; said fifteenth grade-separated crossing being disposedintermediately along the traveled length of said second road surfacebetween said twelfth grade-separated crossing and said sixteenthgrade-separated crossing; said sixteenth grade-separated crossing beingdisposed intermediately along the traveled length of said second roadsurface between said fifteenth grade-separated crossing and said thirdgrade-separated crossing; said seventeenth grade-separated crossingbeing disposed intermediately along the traveled length of said fifthroad surface between said sixth grade-separated crossing and saideighteenth grade-separated crossing; said eighteenth grade-separatedcrossing being disposed intermediately along the traveled length of saidfifth road surface between said seventeenth grade-separated crossing andsaid ninth grade-separated crossing; said nineteenth grade-separatedcrossing being disposed intermediately along the traveled length of saidsixth road surface between said tenth grade-separated crossing and saidtwentieth grade-separated crossing; said twentieth grade-separatedcrossing being disposed intermediately along the traveled length of saidsixth road surface between said nineteenth grade-separated crossing andsaid seventh grade-separated crossing; said twenty-first grade-separatedcrossing being disposed intermediately along the traveled length of saidseventh road surface between said sixteenth grade-separated crossing andsaid twenty-second grade-separated crossing; and said twenty-fourthgrade-separated crossing being disposed intermediately along thetraveled length of said eighth road surface between said twenty-thirdgrade-separated crossing and said fifteenth grade-separated crossing. 4.The road junction of claim 1, further comprising: a seventh road surfaceextending from said third extremity of the junction to said firstextremity of the junction; an eighth road surface extending from saidfourth extremity of the junction to said second extremity of thejunction; at said first extremity of the junction, said second roadsurface being disposed laterally between said seventh and first roadsurfaces; at said third extremity of the junction, said third roadsurface being disposed laterally between said fourth and seventh roadsurfaces; at said fourth extremity of the junction, said fourth roadsurface being disposed laterally between said third and eighth roadsurfaces; at said second extremity of the junction, said first roadsurface being disposed laterally between said second and eighth roadsurfaces; said first road surface intersecting said eighth road surfaceat a thirteenth grade-separated crossing; said first road surfaceintersecting said seventh road surface at a fourteenth grade-separatedcrossing; said second road surface intersecting said seventh roadsurface at a fifteenth grade-separated crossing; said second roadsurface intersecting said eighth road surface at a sixteenthgrade-separated crossing; said fifth road surface intersecting saideighth road surface at a seventeenth grade-separated crossing; saidfifth road surface intersecting said seventh road surface at aneighteenth grade-separated crossing; said sixth road surfaceintersecting said seventh road surface at a nineteenth grade-separatedcrossing; said sixth road surface intersecting said eighth road surfaceat a twentieth grade-separated crossing; said seventh road surfaceintersecting said third road surface at a twenty-first grade-separatedcrossing; said seventh road surface intersecting said fourth roadsurface at a twenty-second grade-separated crossing; said seventh roadsurface intersecting said eighth road surface at a twenty-thirdgrade-separated crossing; said eighth road surface intersecting saidfourth road surface at a twenty-fourth grade-separated crossing; saideighth road surface intersecting said third road surface at atwenty-fifth grade-separated crossing; said eighth road surfaceintersecting said seventh road surface at a twenty-sixth grade-separatedcrossing; said thirteenth grade-separated crossing being disposedintermediately along the traveled length of said first road surfacebetween said first extremity of the junction and said firstgrade-separated crossing; said fourteenth grade-separated crossing beingdisposed intermediately along the traveled length of said first roadsurface between said second grade-separated crossing and said ninthgrade-separated crossing; said fifteenth grade-separated crossing beingdisposed intermediately along the traveled length of said second roadsurface between said twelfth grade-separated crossing and said thirdgrade-separated crossing; said sixteenth grade-separated crossing beingdisposed intermediately along the traveled length of said second roadsurface between said fourth grade-separated crossing and said firstextremity of the junction; said seventeenth grade-separated crossingbeing disposed intermediately along the traveled length of said fifthroad surface between said first extremity of the junction and said fifthgrade-separated crossing; said eighteenth grade-separated crossing beingdisposed intermediately along the traveled length of said fifth roadsurface between said sixth grade-separated crossing and said ninthgrade-separated crossing; said nineteenth grade-separated crossing beingdisposed intermediately along the traveled length of said sixth roadsurface between said tenth grade-separated crossing and said seventhgrade-separated crossing; said eighth grade-separated crossing beingdisposed intermediately along the traveled length of said sixth roadsurface between said seventh grade-separated crossing and said twentiethgrade-separated crossing; said nineteenth grade-separated crossing beingdisposed intermediately along the traveled length of said seventh roadsurface between said twenty-sixth grade-separated crossing and saideighteenth grade-separated crossing; said twenty-first grade-separatedcrossing being disposed intermediately along the traveled length of saidseventh road surface between said fifteenth grade-separated crossing andsaid twenty-second grade-separated crossing; said twenty-secondgrade-separated crossing being disposed intermediately along thetraveled length of said seventh road surface between said twenty-firstgrade-separated crossing and said twenty-third grade-separated crossing;said sixteenth grade-separated crossing being disposed intermediatelyalong the traveled length of said eighth road surface between saidtwenty-third grade-separated crossing and said thirteenthgrade-separated crossing; said twenty-fourth grade-separated crossingbeing disposed intermediately along the traveled length of said eighthroad surface between said twentieth grade-separated crossing and saidtwenty-fifth grade-separated crossing; and said twenty-fifthgrade-separated crossing being disposed intermediately along thetraveled length of said eighth road surface between said twenty-fourthgrade-separated crossing and said twenty-sixth grade-separated crossing.5. The road junction of claim 1, further comprising: a seventh roadsurface extending from said third extremity of the junction to saidfirst extremity of the junction; an eighth road surface extending fromsaid fourth extremity of the junction to said second extremity of thejunction; at said first extremity of the junction, said second roadsurface being disposed laterally between said seventh and first roadsurfaces; at said third extremity of the junction, said third roadsurface being disposed laterally between said fourth and seventh roadsurfaces; at said fourth extremity of the junction, said fourth roadsurface being disposed laterally between said third and eighth roadsurfaces; at said second extremity of the junction, said first roadsurface being disposed laterally between said second and eighth roadsurfaces; said first road surface intersecting said eighth road surfaceat a thirteenth grade-separated crossing; said first road surfaceintersecting said seventh road surface at a fourteenth grade-separatedcrossing; said second road surface intersecting said seventh roadsurface at a fifteenth grade-separated crossing; said second roadsurface intersecting said eighth road surface at a sixteenthgrade-separated crossing; said fifth road surface intersecting saideighth road surface at a seventeenth grade-separated crossing; saidfifth road surface intersecting said seventh road surface at aneighteenth grade-separated crossing; said sixth road surfaceintersecting said seventh road surface at a nineteenth grade-separatedcrossing; said sixth road surface intersecting said eighth road surfaceat a twentieth grade-separated crossing; said eighth road surfaceintersecting said eighth road surface at a twenty-first grade-separatedcrossing; said eighth road surface intersecting said fourth road surfaceat a twenty-second grade-separated crossing; said eighth road surfaceintersecting said third road surface at a twenty-third grade-separatedcrossing; said eighth road surface intersecting said seventh roadsurface at a twenty-fourth grade-separated crossing; said seventh roadsurface intersecting said third road surface at a twenty-fifthgrade-separated crossing; said seventh road surface intersecting saidfourth road surface at a twenty-sixth grade-separated crossing; saidseventh road surface intersecting said eighth road surface at atwenty-seventh grade-separated crossing; said thirteenth grade-separatedcrossing being disposed intermediately along the traveled length of saidfirst road surface between said first extremity of the junction and saidfirst grade-separated crossing; said fourteenth grade-separated crossingbeing disposed intermediately along the traveled length of said firstroad surface between said second grade-separated crossing and said ninthgrade-separated crossing; said fifteenth grade-separated crossing beingdisposed intermediately along the traveled length of said second roadsurface between said twelfth grade-separated crossing and said thirdgrade-separated crossing; said sixteenth grade-separated crossing beingdisposed intermediately along the traveled length of said second roadsurface between said fourth grade-separated crossing and said firstextremity of the junction; said seventeenth grade-separated crossingbeing disposed intermediately along the traveled length of said fifthroad surface between said first extremity of the junction and said fifthgrade-separated crossing; said eighteenth grade-separated crossing beingdisposed intermediately along the traveled length of said fifth roadsurface between said sixth grade-separated crossing and said ninthgrade-separated crossing; said nineteenth grade-separated crossing beingdisposed intermediately along the traveled length of said sixth roadsurface between said tenth grade-separated crossing and said seventhgrade-separated crossing; said eighth grade-separated crossing beingdisposed intermediately along the traveled length of said sixth roadsurface between said seventh grade-separated crossing and said twentiethgrade-separated crossing; said nineteenth grade-separated crossing beingdisposed intermediately along the traveled length of said seventh roadsurface between said twenty-fourth grade-separated crossing and saideighteenth grade-separated crossing; said twenty-fifth grade-separatedcrossing being disposed intermediately along the traveled length of saidseventh road surface between said fifteenth grade-separated crossing andsaid twenty-sixth grade-separated crossing; said twenty-sixthgrade-separated crossing being disposed intermediately along thetraveled length of said seventh road surface between said twenty-fifthgrade-separated crossing and said twenty-seventh grade-separatedcrossing; said twenty-first grade-separated crossing being disposedintermediately along the traveled length of said eighth road surfacebetween said twentieth grade-separated crossing and said twenty-secondgrade-separated crossing; said twenty-second grade-separated crossingbeing disposed intermediately along the traveled length of said eighthroad surface between said twenty-first grade-separated crossing and saidtwenty-third grade-separated crossing; and said twenty-thirdgrade-separated crossing being disposed intermediately along thetraveled length of said eighth road surface between said twenty-secondgrade-separated crossing and said twenty-fourth grade-separatedcrossing.
 6. The road junction of claim 1, further comprising: a seventhroad surface extending from said third extremity of the junction to saidfirst extremity of the junction; an eighth road surface extending fromsaid fourth extremity of the junction to said second extremity of thejunction; at said first extremity of the junction, said second roadsurface being disposed laterally between said seventh and first roadsurfaces; at said third extremity of the junction, said third roadsurface being disposed laterally between said fourth and seventh roadsurfaces; at said fourth extremity of the junction, said fourth roadsurface being disposed laterally between said third and eighth roadsurfaces; at said second extremity of the junction, said first roadsurface being disposed laterally between said second and eighth roadsurfaces; said first road surface intersecting said eighth road surfaceat a thirteenth grade-separated crossing; said first road surfaceintersecting said seventh road surface at a fourteenth grade-separatedcrossing; said second road surface intersecting said seventh roadsurface at a fifteenth grade-separated crossing; said second roadsurface intersecting said eighth road surface at a sixteenthgrade-separated crossing; said fifth road surface intersecting saideighth road surface at a seventeenth grade-separated crossing; saidfifth road surface intersecting said seventh road surface at aneighteenth grade-separated crossing; said sixth road surfaceintersecting said seventh road surface at a nineteenth grade-separatedcrossing; said sixth road surface intersecting said eighth road surfaceat a twentieth grade-separated crossing; said seventh road surfaceintersecting said seventh road surface at a twenty-first grade-separatedcrossing; said seventh road surface intersecting said third road surfaceat a twenty-second grade-separated crossing; said seventh road surfaceintersecting said fourth road surface at a twenty-third grade-separatedcrossing; said eighth road surface intersecting said seventh roadsurface at a twenty-fourth grade-separated crossing; said eighth roadsurface intersecting said fourth road surface at a twenty-fifthgrade-separated crossing; said eighth road surface intersecting saidthird road surface at a twenty-sixth grade-separated crossing; saideighth road surface intersecting said seventh road surface at atwenty-seventh grade-separated crossing; said thirteenth grade-separatedcrossing being disposed intermediately along the traveled length of saidfirst road surface between said first extremity of the junction and saidfirst grade-separated crossing; said fourteenth grade-separated crossingbeing disposed intermediately along the traveled length of said firstroad surface between said second grade-separated crossing and said ninthgrade-separated crossing; said fifteenth grade-separated crossing beingdisposed intermediately along the traveled length of said second roadsurface between said twelfth grade-separated crossing and said thirdgrade-separated crossing; said sixteenth grade-separated crossing beingdisposed intermediately along the traveled length of said second roadsurface between said fourth grade-separated crossing and said firstextremity of the junction; said seventeenth grade-separated crossingbeing disposed intermediately along the traveled length of said fifthroad surface between said first extremity of the junction and said fifthgrade-separated crossing; said eighteenth grade-separated crossing beingdisposed intermediately along the traveled length of said fifth roadsurface between said sixth grade-separated crossing and said ninthgrade-separated crossing; said nineteenth grade-separated crossing beingdisposed intermediately along the traveled length of said sixth roadsurface between said tenth grade-separated crossing and said seventhgrade-separated crossing; said eighth grade-separated crossing beingdisposed intermediately along the traveled length of said sixth roadsurface between said seventh grade-separated crossing and said twentiethgrade-separated crossing; said nineteenth grade-separated crossing beingdisposed intermediately along the traveled length of said seventh roadsurface between said twenty-seventh grade-separated crossing and saideighteenth grade-separated crossing; said twenty-first grade-separatedcrossing being disposed intermediately along the traveled length of saidseventh road surface between said fifteenth grade-separated crossing andsaid twenty-second grade-separated crossing; said twenty-secondgrade-separated crossing being disposed intermediately along thetraveled length of said seventh road surface between said twenty-firstgrade-separated crossing and said twenty-third grade-separated crossing;said twenty-third grade-separated crossing being disposed intermediatelyalong the traveled length of said seventh road surface between saidtwenty-second grade-separated crossing and said twenty-fourthgrade-separated crossing; said sixteenth grade-separated crossing beingdisposed intermediately along the traveled length of said eighth roadsurface between said twenty-fourth grade-separated crossing and saidthirteenth grade-separated crossing; said twenty-fifth grade-separatedcrossing being disposed intermediately along the traveled length of saideighth road surface between said twentieth grade-separated crossing andsaid twenty-sixth grade-separated crossing; and said twenty-sixthgrade-separated crossing being disposed intermediately along thetraveled length of said eighth road surface between said twenty-fifthgrade-separated crossing and said twenty-seventh grade-separatedcrossing.
 7. The road junction of claim 3, further comprising: a ninthroad surface extending from said first extremity of the junction andreturning to said first extremity of the junction; a tenth road surfaceextending from said second extremity of the junction and returning tosaid second extremity of the junction; an eleventh road surfaceextending from said third extremity of the junction and returning tosaid third extremity of the junction; a twelfth road surface extendingfrom said fourth extremity of the junction and returning to said fourthextremity of the junction; at said first extremity of the junction, saidninth road surface being disposed laterally between said first and fifthroad surfaces; and at said first extremity of the junction, said ninthroad surface being disposed laterally between said seventh and secondroad surfaces; at said second extremity of the junction, said tenth roadsurface being disposed laterally between said second and sixth roadsurfaces; and at said second extremity of the junction, said tenth roadsurface being disposed laterally between said eighth and first roadsurfaces; at said third extremity of the junction, said eleventh roadsurface being disposed laterally between said third and seventh roadsurfaces; and at said third extremity of the junction, said eleventhroad surface being disposed laterally between said sixth and fourth roadsurfaces; at said fourth extremity of the junction, said twelfth roadsurface being disposed laterally between said fourth and eighth roadsurfaces; and at said fourth extremity of the junction, said twelfthroad surface being disposed laterally between said fifth and third roadsurfaces; said first road surface intersecting said eleventh roadsurface at a twenty-fifth grade-separated crossing; said first roadsurface intersecting said eleventh road surface at a twenty-sixthgrade-separated crossing; said first road surface intersecting saidninth road surface at a twenty-seventh grade-separated crossing; saidfirst road surface intersecting said tenth road surface at atwenty-eighth grade-separated crossing; said second road surfaceintersecting said tenth road surface at a twenty-ninth grade-separatedcrossing; said second road surface intersecting said ninth road surfaceat a thirtieth grade-separated crossing; said second road surfaceintersecting said eleventh road surface at a thirty-firstgrade-separated crossing; and said second road surface intersecting saideleventh road surface at a thirty-second grade-separated crossing; saidfifth road surface intersecting said eleventh road surface at athirty-third grade-separated crossing; and said fifth road surfaceintersecting said eleventh road surface at a thirty-fourthgrade-separated crossing; said sixth road surface intersecting saideleventh road surface at a thirty-fifth grade-separated crossing; andsaid sixth road surface intersecting said eleventh road surface at athirty-sixth grade-separated crossing; said seventh road surfaceintersecting said ninth road surface at a thirty-seventh grade-separatedcrossing; and said seventh road surface intersecting said ninth roadsurface at a thirty-eighth grade-separated crossing; said eighth roadsurface intersecting said ninth road surface at a thirty-ninthgrade-separated crossing; and said eighth road surface intersecting saidninth road surface at a fortieth grade-separated crossing; said ninthroad surface intersecting said eleventh road surface at a forty-firstgrade-separated crossing; and said ninth road surface intersecting saideleventh road surface at a forty-second grade-separated crossing; andsaid ninth road surface intersecting said eleventh road surface at aforty-third grade-separated crossing; and said ninth road surfaceintersecting said eleventh road surface at a forty-fourthgrade-separated crossing; said third road surface intersecting saideleventh road surface at a forty-fifth grade-separated crossing; saidfourth road surface intersecting said eleventh road surface at aforty-sixth grade-separated crossing; said fourth road surfaceintersecting said twelfth road surface at a forty-seventhgrade-separated crossing; said third road surface intersecting saidtwelfth road surface at a forty-eighth grade-separated crossing; saidfourth road surface intersecting said ninth road surface at aforty-ninth grade-separated crossing; said third road surfaceintersecting said ninth road surface at a fiftieth grade-separatedcrossing; and said third road surface intersecting said ninth roadsurface at a fifty-first grade-separated crossing; said fourth roadsurface intersecting said ninth road surface at a fifty-secondgrade-separated crossing; said first grade-separated crossing beingdisposed intermediately along the traveled length of said first roadsurface between said twenty-fifth grade-separated crossing and saidsecond grade-separated crossing; said twenty-sixth grade-separatedcrossing being disposed intermediately along the traveled length of saidfirst road surface between said second grade-separated crossing and saidthirteenth grade-separated crossing; said twenty-seventh grade-separatedcrossing being disposed intermediately along the traveled length of saidfirst road surface between said fourteenth grade-separated crossing andsaid ninth grade-separated crossing; said tenth grade-separated crossingbeing disposed intermediately along the traveled length of said firstroad surface between said ninth grade-separated crossing and saidtwenty-eighth grade-separated crossing; said eleventh grade-separatedcrossing being disposed intermediately along the traveled length of saidsecond road surface between said twenty-ninth grade-separated crossingand said twelfth grade-separated crossing; said thirtieth sixthgrade-separated crossing being disposed intermediately along thetraveled length of said second road surface between said twelfthgrade-separated crossing and said fifteenth grade-separated crossing;said thirty-first grade-separated crossing being disposed intermediatelyalong the traveled length of said second road surface between saidsixteenth grade-separated crossing and said third grade-separatedcrossing; said fourth grade-separated crossing being disposedintermediately along the traveled length of said second road surfacebetween said third grade-separated crossing and said thirty-secondgrade-separated crossing; said fiftieth grade-separated crossing beingdisposed intermediately along the traveled length of said third roadsurface between said sixth grade-separated crossing and said secondgrade-separated crossing; said fifty-first grade-separated crossingbeing disposed intermediately along the traveled length of said thirdroad surface between said third grade-separated crossing and saidforty-fifth grade-separated crossing; said forty-fifth grade-separatedcrossing being disposed intermediately along the traveled length of saidthird road surface between said fifty-first grade-separated crossing andsaid twenty-first grade-separated crossing; said twenty-fourthgrade-separated crossing being disposed intermediately along thetraveled length of said third road surface between said twenty-firstgrade-separated crossing and said forty-eighth grade-separated crossing;said twenty-third grade-separated crossing being disposed intermediatelyalong the traveled length of said fourth road surface between saidforty-seventh grade-separated crossing and said twenty-secondgrade-separated crossing; said forty-sixth grade-separated crossingbeing disposed intermediately along the traveled length of said fourthroad surface between said twenty-second grade-separated crossing andsaid fifty-second grade-separated crossing; said fifty-secondgrade-separated crossing being disposed intermediately along thetraveled length of said fourth road surface between said forty-sixthgrade-separated crossing and said fourth grade-separated crossing; saidforty-ninth grade-separated crossing being disposed intermediately alongthe traveled length of said fourth road surface between said firstgrade-separated crossing and said fifth grade-separated crossing; saidfifth grade-separated crossing being disposed intermediately along thetraveled length of said fifth road surface between said thirty-thirdgrade-separated crossing and said sixth grade-separated crossing; saidthirty-fourth grade-separated crossing being disposed intermediatelyalong the traveled length of said fifth road surface between said sixthgrade-separated crossing and said seventeenth grade-separated crossing;said thirty-fifth grade-separated crossing being disposed intermediatelyalong the traveled length of said sixth road surface between saidtwentieth grade-separated crossing and said seventh grade-separatedcrossing; said eighth grade-separated crossing being disposedintermediately along the traveled length of said sixth road surfacebetween said seventh grade-separated crossing and said thirty-sixthgrade-separated crossing; said thirty-seventh grade-separated crossingbeing disposed intermediately along the traveled length of said seventhroad surface between said seventeenth grade-separated crossing and saidthirteenth grade-separated crossing; said thirty-eighth grade-separatedcrossing being disposed intermediately along the traveled length of saidseventh road surface between said sixteenth grade-separated crossing andsaid twenty-first grade-separated crossing; said thirty-ninthgrade-separated crossing being disposed intermediately along thetraveled length of said eighth road surface between said twenty-fourthgrade-separated crossing and said fifteenth grade-separated crossing;said fortieth grade-separated crossing being disposed intermediatelyalong the traveled length of said eighth road surface between saidfourteenth grade-separated crossing and said eighteenth grade-separatedcrossing; said forty-ninth grade-separated crossing being disposedintermediately along the traveled length of said ninth road surfacebetween said forty-first grade-separated crossing and said fiftiethgrade-separated crossing; said fiftieth grade-separated crossing beingdisposed intermediately along the traveled length of said ninth roadsurface between said forty-ninth grade-separated crossing and saidforty-second grade-separated crossing; said forty-second grade-separatedcrossing being disposed intermediately along the traveled length of saidninth road surface between said fiftieth grade-separated crossing andsaid thirty-seventh grade-separated crossing; said thirty-seventhgrade-separated crossing being disposed intermediately along thetraveled length of said ninth road surface between said forty-secondgrade-separated crossing and said fortieth grade-separated crossing;said fortieth grade-separated crossing being disposed intermediatelyalong the traveled length of said ninth road surface between saidthirty-seventh grade-separated crossing and said twenty-seventhgrade-separated crossing; said twenty-seventh grade-separated crossingbeing disposed intermediately along the traveled length of said ninthroad surface between said fortieth grade-separated crossing and saidthirtieth grade-separated crossing; said thirtieth grade-separatedcrossing being disposed intermediately along the traveled length of saidninth road surface between said twenty-seventh grade-separated crossingand said thirty-ninth grade-separated crossing; said thirty-ninthgrade-separated crossing being disposed intermediately along thetraveled length of said ninth road surface between said thirtiethgrade-separated crossing and said thirty-eighth grade-separatedcrossing; said thirty-eighth grade-separated crossing being disposedintermediately along the traveled length of said ninth road surfacebetween said thirty-ninth grade-separated crossing and said forty-thirdgrade-separated crossing; said forty-third grade-separated crossingbeing disposed intermediately along the traveled length of said ninthroad surface between said thirty-eighth grade-separated crossing andsaid fifty-first grade-separated crossing; said fifty-firstgrade-separated crossing being disposed intermediately along thetraveled length of said ninth road surface between said forty-thirdgrade-separated crossing and said fifty-second grade-separated crossing;said fifty-second grade-separated crossing being disposed intermediatelyalong the traveled length of said ninth road surface between saidfifty-first grade-separated crossing and said forty-fourthgrade-separated crossing; said thirty-fourth grade-separated crossingbeing disposed intermediately along the traveled length of said eleventhroad surface between said thirty-fifth grade-separated crossing and saidforty-second grade-separated crossing; and said thirty-thirdgrade-separated crossing being disposed intermediately along thetraveled length of said eleventh road surface between said forty-firstgrade-separated crossing and said thirty-sixth grade-separated crossing.8. The road junction of claim 1, wherein said first, or second, orthird, or fourth road surfaces is omitted, or first and third, or firstand fourth, or second and third, or second and fourth road surfaces areomitted.
 9. The road junction of claim 2, wherein said first, or second,or third, or fourth, or seventh, or eighth road surfaces is omitted, orfirst and third, or first and fourth, or first and seventh, or first andeighth, or second and third, or second and fourth, or second andseventh, or second and eighth, third and seventh, or third and eighth,or fourth and seventh, or fourth and eighth, or first and seventh andthird, or first and seventh and fourth, or first and eighth and third,or first and eighth and fourth, or second and seventh and third, orsecond and seventh and fourth, or second and eighth and third, or secondand eight and fourth road surfaces are omitted.
 10. The road junction ofclaim 3, wherein said first, or second, or third, or fourth, or seventh,or eighth road surfaces is omitted, or first and third, or first andfourth, or first and seventh, or first and eighth, or second and third,or second and fourth, or second and seventh, or second and eighth, thirdand seventh, or third and eighth, or fourth and seventh, or fourth andeighth, or first and seventh and third, or first and seventh and fourth,or first and eighth and third, or first and eighth and fourth, or secondand seventh and third, or second and seventh and fourth, or second andeighth and third, or second and eight and fourth road surfaces areomitted.
 11. The road junction of claim 4, wherein said first, orsecond, or third, or fourth, or seventh, or eighth road surfaces isomitted, or first and third, or first and fourth, or first and seventh,or first and eighth, or second and third, or second and fourth, orsecond and seventh, or second and eighth, third and seventh, or thirdand eighth, or fourth and seventh, or fourth and eighth, or first andseventh and third, or first and seventh and fourth, or first and eighthand third, or first and eighth and fourth, or second and seventh andthird, or second and seventh and fourth, or second and eighth and third,or second and eight and fourth road surfaces are omitted.
 12. The roadjunction of claim 5, wherein said first, or second, or third, or fourth,or seventh, or eighth road surfaces is omitted, or first and third, orfirst and fourth, or first and seventh, or first and eighth, or secondand third, or second and fourth, or second and seventh, or second andeighth, third and seventh, or third and eighth, or fourth and seventh,or fourth and eighth, or first and seventh and third, or first andseventh and fourth, or first and eighth and third, or first and eighthand fourth, or second and seventh and third, or second and seventh andfourth, or second and eighth and third, or second and eight and fourthroad surfaces are omitted.
 13. The road junction of claim 6, whereinsaid first, or second, or third, or fourth, or seventh, or eighth roadsurfaces is omitted, or first and third, or first and fourth, or firstand seventh, or first and eighth, or second and third, or second andfourth, or second and seventh, or second and eighth, third and seventh,or third and eighth, or fourth and seventh, or fourth and eighth, orfirst and seventh and third, or first and seventh and fourth, or firstand eighth and third, or first and eighth and fourth, or second andseventh and third, or second and seventh and fourth, or second andeighth and third, or second and eight and fourth road surfaces areomitted.
 14. The road junction of claim 7, wherein one or more of saidfirst, third, seventh, eighth, ninth, tenth, eleventh, or twelfth roadsurfaces, or one or more of said first, fourth, seventh, eighth, ninth,tenth, eleventh, or twelfth road surfaces, or one or more of saidsecond, third, seventh, eighth, ninth, tenth, eleventh, or twelfth roadsurfaces, or one or more of said second, fourth, seventh, eighth, ninth,tenth, eleventh, or twelfth road surfaces are omitted.